In the shingle art, it is known to make molded shingles that have the appearance of natural materials, such as slate, for example, in that natural-appearing surface configurations can be molded into a shingle, to simulate the natural materials. Such shingles may be constructed in accordance with any of U.S. Pat. Nos. 7,141,200; 7,141,201; 6,808,785 and published International Application WO 2008/052029, the complete disclosures of which are herein incorporated by reference.
Such shingles are generally rigid and are molded of a polymer based material.
When such shingles are laid up on a roof, in courses, wind driven moisture including rain, snow and even moist air can be driven to the fastener locations, traveling along relatively smooth or textured surfaces of the shingles. Such moisture can infiltrate around fasteners that are used to fasten the shingles to a roof. Generally, such fasteners, such as nails, staples or the like penetrate fastener locations of the shingles, in order to fasten the shingles to a roof. Such fastener locations generally include depressions in the upper surfaces of the shingles. Usually, such depressions in shingles have little or no drainage facilities. Over extended periods of time such fasteners, generally of metal construction, when contacted with moisture, can experience degradation of the fastener, such as rusting, oxidation, or other degradation.